Reheating the Universe after string theory inflation
Abstract
In string theory realizations of inflation, the endpoint of inflation is often braneantibrane annihilation. We consider the processes of reheating of the standard model universe after brane inflation. We identify the channels of inflaton energy decay, cascading from tachyon annihilation through massive closed string loops, KK modes, and brane displacement moduli to the lighter standard model particles. Cosmological data constrains scenarios by putting stringent limits on the fraction of reheating energy deposited in gravitons and nonstandard sector massive relics. We estimate the energy deposited into various light degrees of freedom in the open and closed string sectors, the timing of reheating, and the reheating temperature. Production of gravitons is significantly suppressed in warped inflation. However, we predict a residual gravitational radiation background at the level {omega}{sub GW}{approx}10{sup 8} of the present cosmological energy density. We also extend our analysis to multiple throat scenarios. A viable reheating would be possible in a single throat or in a certain subclass of multiple throat scenarios of the KKLMMT type inflation model, but overproduction of massive KaluzaKlein (KK) modes poses a serious problem. The problem is quite severe if some inner manifold comes with approximate isometries (angular KK modes) or if there exists amore »
 Authors:
 Canadian Institute for Theoretical Astrophysics, 60 St George Str, Toronto, Ontario, M5S 3H8 (Canada)
 School of Physics, Korea Institute for Advanced Study, 20743, CheongryangriDong, DongdaemunGu, Seoul 130722 (Korea, Republic of)
 Publication Date:
 OSTI Identifier:
 20711597
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 72; Journal Issue: 10; Other Information: DOI: 10.1103/PhysRevD.72.106001; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANNIHILATION; COSMOLOGY; DECAY; DEGREES OF FREEDOM; ENERGY DENSITY; GRAVITATIONAL WAVES; GRAVITONS; KALUZAKLEIN THEORY; MEMBRANES; STANDARD MODEL; STRING MODELS; UNIVERSE
Citation Formats
Kofman, Lev, and Yi, Piljin. Reheating the Universe after string theory inflation. United States: N. p., 2005.
Web. doi:10.1103/PhysRevD.72.106001.
Kofman, Lev, & Yi, Piljin. Reheating the Universe after string theory inflation. United States. doi:10.1103/PhysRevD.72.106001.
Kofman, Lev, and Yi, Piljin. Tue .
"Reheating the Universe after string theory inflation". United States.
doi:10.1103/PhysRevD.72.106001.
@article{osti_20711597,
title = {Reheating the Universe after string theory inflation},
author = {Kofman, Lev and Yi, Piljin},
abstractNote = {In string theory realizations of inflation, the endpoint of inflation is often braneantibrane annihilation. We consider the processes of reheating of the standard model universe after brane inflation. We identify the channels of inflaton energy decay, cascading from tachyon annihilation through massive closed string loops, KK modes, and brane displacement moduli to the lighter standard model particles. Cosmological data constrains scenarios by putting stringent limits on the fraction of reheating energy deposited in gravitons and nonstandard sector massive relics. We estimate the energy deposited into various light degrees of freedom in the open and closed string sectors, the timing of reheating, and the reheating temperature. Production of gravitons is significantly suppressed in warped inflation. However, we predict a residual gravitational radiation background at the level {omega}{sub GW}{approx}10{sup 8} of the present cosmological energy density. We also extend our analysis to multiple throat scenarios. A viable reheating would be possible in a single throat or in a certain subclass of multiple throat scenarios of the KKLMMT type inflation model, but overproduction of massive KaluzaKlein (KK) modes poses a serious problem. The problem is quite severe if some inner manifold comes with approximate isometries (angular KK modes) or if there exists a throat of modest length other than the standard model throat, possibly associated with some hidden sector (lowlying KK modes)},
doi = {10.1103/PhysRevD.72.106001},
journal = {Physical Review. D, Particles Fields},
number = 10,
volume = 72,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}

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